Evidence-based medicine penetrates poorly into clinical practice, resulting in a large amount of wasted resources and increased morbidity and mortality from inappropriate or inefficient medical care. Computerized decision support has been shown to substantially improve this process in multiple venues. Preliminary work has shown that pediatric gastroenterology as a specialty shows substantial variation in care nationally, indicating the need for measures to aid providers in the use of evidence-based guidelines. Our research group has developed a large, robust computerized decision support system for use in pediatric primary care: the Child Health Improvement through Computerized Automation (CHICA). The primary goal of this application is to adapt this system for use in a pediatric subspecialty setting (CHICA-GI) and study its effects on adherence to evidence-based medicine and on clinical outcomes. The hypothesis of this application is that the introduction of an evidence-based computerized decision support system into pediatric gastroenterology care will improve adherence to guidelines, as well as general health outcomes. This hypothesis will be tested by accomplishing the following specific aims: Gain knowledge and expertise about the CHICA system currently utilized in the primary care setting by modifying the system to support a pediatric gastroenterology guideline for constipation in a primary care setting (Aim 1). Build a new version of the CHICA system for use in the pediatric gastroenterology outpatient clinic setting (CHICA-GI) (Aim 2). Modify the newly built CHICA-GI system to support multiple pediatric gastroenterology guidelines and determine if the CHICA-GI CDSS improves adherence to the three evidence-based guidelines as well as patient level outcomes (Aim 3). Furthermore, the career development goals of this application include intensive training in medical informatics, as well as immersion in a mentoring environment surrounded by established physician-investigators in health services, informatics, and pediatric gastroenterology. At the end of this project, I will have built and intensively studied a unique computerized decision support system in pediatric gastroenterology and will be poised to create the next generation of systems necessary to bridge the gap between clinical practice and research.